http://firstmonday.org/issues/issue7_11/tuomi/index.html First Monday The Lives and Death of Moore's Law by Ilkka Tuomi Abstract Moore's Law has been an important benchmark for developments in microelectronics and information processing for over three decades. During this time, its applications and interpretations have proliferated and expanded, often far beyond the validity of the original assumptions made by Moore. Technical considerations of optimal chip manufacturing costs have been expanded to processor performance, economics of computing, and social development. It is therefore useful to review the various interpretations of Moore's Law and empirical evidence that could support them. Such an analysis reveals that semiconductor technology has evolved during the last four decades under very special economic conditions. In particular, the rapid development of microelectronics implies that economic and social demand has played a limited role in this industry. Contrary to popular claims, it appears that the common versions of Moore's Law have not been valid during the last decades. As semiconductors are becoming important in economy and society, Moore's Law is now becoming an increasingly misleading predictor of future developments. Contents 1. Introduction 2. Moore's original formulation 3. Reformulations of Moore's Law 4. Losing the memory 5. Empirical evidence on Moore's Law 6. Computers and development 1. Introduction In 1965, Gordon Moore, Director of Fairchild Semiconductor's Research and Development Laboratories, wrote an article on the future development of semiconductor industry for the 35th anniversary issue of Electronics magazine. In the article, Moore noted that the complexity of minimum cost semiconductor components had doubled per year since the first prototype microchip was produced in 1959. This exponential increase in the number of components on a chip became later known as Moore's Law. In the 1980s, Moore's Law started to be described as the doubling of number of transistors on a chip every 18 months. At the beginning of the 1990s, Moore's Law became commonly interpreted as the doubling of microprocessor power every 18 months. In the 1990s, Moore's Law became widely associated with the claim that computing power at fixed cost is doubling every 18 months. Moore's Law has mainly been used to highlight the rapid change in information processing technologies. The growth in chip complexity and fast reduction in manufacturing costs have meant that technological advances have become important factors in economic, organizational, and social change. In fact, during the last decades a good first approximation for long-range planning has often been that information processing capacity is essentially free and technical possibilities are unlimited. Regular doubling means exponential growth. Exponential growth, however, also means that the fundamental physical limits of microelectronics are approaching rapidly. Several observers have therefore speculated about the possibility of "the end of Moore's Law." Often these speculations have concluded by noting that Moore's Law will probably be valid for at least "a few more generations of technology," or about a decade. An important example is the International Technology Roadmap for Semiconductors (ITRS), which now extends to 2016. This roadmap is generated by a global group of experts and represents their consensus. Although it notes that within the next 10-15 years "most of the known technological capabilities will approach or have reached their limits," its basic assumption is that Moore's Law, although perhaps slowing down, still provides a good basis for predicting future developments in the semiconductor industry (ITRS, 2001) [ 1]. Of course, if Moore's Law is valid, independent of the exact nature of physical limits, exponential development means that the limits are only a few technological generations ahead. Order of magnitude errors in our current estimates of the ultimate limits of chip technology will create at most a few months of error in the time when they become bottlenecks in chip technology [ 2]. As a result, it is easy to predict that Moore's Law will become invalid soon. Speculations on the extended lifetime of Moore's Law are therefore often centered on quantum computing, bio-computing, DNA computers, and other theoretically possible information processing mechanisms. Such extensions, obviously, extend beyond semiconductor industry and the domain of Moore's Law. Indeed, it could be difficult to define a "component" or a "chip" in those future devices. Although discussion on physical limits, bottlenecks, and alternative information processing models may be important for chip manufacturers, it is, however, not the focus of this paper. Instead, I shall argue that there is no end to Moore's Law in sight simply because it never accurately described developments in microelectronics. It never was valid. Furthermore, it neglected factors that are becoming increasingly visible and important. The present paper argues that Moore's Law has not been a driver in the development of microelectronics or information technology. This may come as a surprise to some who have learned that Moore's Law has become a self-fulfilling prophecy that semiconductor industry firms have to follow if they want to survive. Instead, I shall argue that technical development in semiconductors during the last four decades has reflected the unique economic and social conditions under which the semiconductor industry has operated. This is important as these conditions are changing. In short, the observed technological trends and their analysis indicate that the semiconductor industry has been a core element in an industry cluster where development to an important extent has been driven by intra-cluster forces. The semiconductor industry, in other words, has been a laboratory of endogenous growth. This laboratory of endogenous growth has also made many failed experiments. Technology has not evolved in the ways predicted by Moore. Moore's Law has become popular partly because it has allowed great flexibility in interpretation and selective choice of supporting data. In this process, Moore's Law and evidence for it have retrospectively been interpreted to establish the validity of the Law. Often the presented evidence has been in visible contradiction with the Law. Technological advances in silicon chips have been relatively independent of end-user needs. During the last three decades, a good approximation in this industry has been that the supply of technology determines development. In economic terms, a key factor underlying the rapid development of semiconductor technology has been a continuous imbalance between supply and demand. It is, however, also clear that no one has exactly been breaking Moore's Law. Strictly speaking there is no such Law. Most discussions that quote Moore's Law are historically inaccurate and extend its scope far beyond available empirical evidence. Indeed, sociologically Moore's Law is a fascinating case of how myths are manufactured in the modern society and how such myths rapidly propagate into scientific articles, speeches of leading industrialists, and government policy reports around the world. It is therefore useful to revisit the evolution of Moore's Law. During its lifetime, its interpretations have involved mainly technical and economic considerations. The following discussion will therefore combine historical, technical, and economic concepts and data. The paper is organized as follows. In the next section, I revisit the original formulation of the Moore's Law and describe its basic assumptions. Section 3 discusses the revisions that Moore made to his original formulation during the 1970s. Section 4 describes the extensions of Moore's Law that became dominant in the 1980s and 1990s. Section 5 then evaluates available evidence to see whether any of the proposed formulations of Moore's Law can be justified. Its subsections review evidence on component counts, microprocessor performance, increase in computing power, and quality-adjusted cost of computing. Section 6 then briefly discusses industrial dynamics that underlie technical development in semiconductors and information processing, and points out some reasons why Moore's Law is becoming increasingly misleading in forecasting future developments in information processing technology. The paper concludes with some general observations on the relation between technical, economic, and social development. <Snip...> -- ----------------- R. A. Hettinga <mailto: rah@ibuc.com> The Internet Bearer Underwriting Corporation <http://www.ibuc.com/> 44 Farquhar Street, Boston, MA 02131 USA "... however it may deserve respect for its usefulness and antiquity, [predicting the end of the world] has not been found agreeable to experience." -- Edward Gibbon, 'Decline and Fall of the Roman Empire'